Diversity-oriented synthesis (DOS) has the potential to empower academic chemists and biologists to explore the relationship between chemistry space and biological activity, leading to major advances in biology and medicine. The Center will perform fundamental research to advance the technology and pathways available for DOS, to help realize its full potential. We will develop a new platform (megabeads) that is optimized for screening by biologists; we will use DOS to discover new catalysts, increasing the range of DOS pathways available; and we will develop several new strategies for library synthesis that explore areas of chemical space that are currently sparsely populated. Two Cores will support the Projects. The Library Synthesis, Formatting and Curation Core will work to automate reaction development, currently the rate-limiting step in DOS, and will make the crucial link to biological screening by providing our libraries to the existing ICCB screening facility in a common format. The Cheminformatics Core will compute molecular descriptors for planned libraries, compare them to a reference set of known molecules, and advise Project researchers on ways to maximize the contribution of a given library to the exploration of chemical space.